The debate over the source of an obnoxious stench that engulfed Tehran on Wednesday is still continuing in the capital city of Iran.
A Tehran city councilor has dismissed claims attributing the foul smell either to an old sealed septic tank on the site of the Plasco building or the capital city's main garbage dump.
A construction manager had said earlier that while digging a hole on the site something erupted with tremendous pressure and let out the obnoxious stench.
Governor General of Tehran, Anoushirvan Mohseni-Bandpey, for his part, believes that a chemical substance with a strong stench has been either deliberately or inadvertently released and engulfed the city in the obnoxious odor.
A day earlier, on Thursday, the local director of the environment department had maintained that the stench smells like a chemical compound named mercaptan.
Known also as methanethiol, mercaptan is a harmless but pungent-smelling gas which has been described as having the stench of rotting cabbages or smelly socks.
It is often added to natural gas, which is colorless and odorless, to make it easier to detect.
The gas company has not yet responded to the allegation.
According to the director of the environmental department of Tehran province, Kioumars Kalantari, the department of water and sewage has been assigned to locate the exact source of the stench that created discomfort for people for three consecutive days.